1. Field of the Invention
This invention relates generally to window and door mounted alarm apparatus, and more particularly to a portable selectively positional intruder alarm for sliding windows and doors which can be installed parallel to the movable window sash or sliding door at selected distances therefrom to provide security while allowing the window to be partially open and will emit an alarm either when the window or door is opened further or when the device is removed from the window or door frame.
2. Brief Description of the Prior Art
Conventional sliding windows, such as single hung, double hung, and xe2x80x9csliderxe2x80x9d windows, are constructed from two window sashes disposed in a common frame. In single hung and double hung windows, a lower window sash slides vertically in its own track relative to an upper window sash. In a xe2x80x9csliderxe2x80x9d window and patio door, a left-hand or right-hand sash slides horizontally in its track relative to a laterally opposed fixed sash. In these types of constructions, one window-sash or door, with its corresponding pane or panes of glass is external to the other. Typically, the upper window sash or fixed window sash is the outer facing member, with respect to the dwelling interior, and when the lower or movable window sash is completely closed, its upper edge is flush with the lower edge of the upper or fixed window sash.
Many people are victimized by intruders that gain entry through sliding windows and doors. Most sliding windows and doors have locks to secure them in a closed position. However few, if any, conventional sliding windows and doors provide for a lock in a partially opened position. It is often desirable to have a sliding window or door partially open to provide cool fresh air and air circulation, but this can sometimes be dangerous because an intruder can simply push the window or door open to gain access to the dwelling.
There are several patents that disclose various devices to lock sliding windows and doors in the closed position, and alarm devices for use on sliding windows and doors. Most prior art intrusion alarms for sliding windows and doors are designed so that they are activated when they are removed from a fully closed window or door, or when the window or door is moved from a fully closed position, and are not capable of providing an alarm function when the window or door is in a partially open position.
Holt, U.S. Pat. No. 4,553,134, Conemac, U.S. Pat. No. 4,888,578, and Neas, U.S. Pat. No. 5,872,514 disclose telescopic tubular alarm devices for sliding windows or doors that are spring biased between the window or door frame and the closed window or door and are activated when removed or an attempt is made to open the closed window or door. These devices are not suited for providing an alarm function when the window or door is in a partially open position, since they are activated when they are compressed.
Blasucci, U.S. Pat. No. 4,149,156 discloses a window alarm employing a releasably mounted plunger switch. The plunger switch is releasably held against the inner surface of the outer section (upper sash) of a double-hung window or sliding door; by a suction cup, in an exemplary embodiment. Movement of the inner section (lower sash) with respect to the outer section (upper sash) dislodges the suction cup, releasing the switch and allowing it to close thereby actuating a signaling means to generate an alarm signal.
Mikiel et al, U.S. Pat. No. 5,552,768 discloses a portable window wedge with alarm comprising a molded resilient triangular block having a suction cup securely fastened to its base. The suction cup is fastened to the base so that a jamming tapered tip on the triangular block is angled slightly toward the mounting surface. The portable sliding window lock is mounted on the vertical surface of a flat window pane adjacent the frame of a sliding window to intercept and jam the window frame with the sliding window partially open. This prevents forcing the partially open window any further open to gain access to an area. An optional feature includes an audible alarm mounted on the resilient triangular block which is set-off by a switch activated by force applied to a sliding glass window engaging the resilient triangular block. The audible alarm is activated by a contact switch, motion sensing switch or pressure switch embedded in the molded resilient triangular block.
Dunagan et al, U.S. Pat. No. 5,164,705 discloses an anti-intrusion window with a built-in alarm comprising a window frame assembly adapted to be attached to a building structure, first and second sash assemblies supported by the frame assembly and relatively movable with respect to each other, a position indicator supported by one sash, a sensor supported by the other sash and an alarm signal generator activated whenever the position indicator and the sensor are at least momentarily adjacent each other. Multiple windows are coupled to a second alarm signal generator which produces an audible alarm when the first alarm signal generator transmits an alarm signal.
The present invention is distinguished over the prior art in general, and these patents in particular by a portable selectively positional intruder alarm for sliding windows and doors that is installed in a window or door frame with its longitudinal axis parallel to a sliding window sash or door at a selected distance therefrom to provide security while allowing the window to be partially open for ventilation and will emit an alarm either when the window or door is opened further or when the device is removed from the window or door frame. The device has a telescoping tubular housing with end plugs at each end. One end plug is fixed to the housing and the other is slidably mounted in the end of the housing. The end plugs are removably held against the opposed tracks of the sliding window sash or sliding door by the force of a compression spring within the housing. An alarm circuit disposed in the outer tube includes a battery, an audio transducer, a normally-open switch, a normally-closed switch, and may also include a visual alarm and battery condition indicator. An actuator pin on the movable frame surface of the sliding window sash or door engages the normally-open switch upon movement of the frame surface a distance toward the housing such that the partially open or fully closed window sash or door may be opened a distance less than the selected distance for ventilation without sounding the alarm and, upon further opening the window sash or door a distance approximate to the selected distance, the alarm is activated. The sliding end plug is engaged with the normally-closed switch when the device is installed in the track and, when the device is removed, is disengaged to activate the alarm.
It is therefore an object of the present invention to provide an intruder alarm for sliding windows and doors, which will provide security while allowing the window or door to be partially open for ventilation and will activate an alarm when the window is opened further.
It is another object of this invention to provide an intruder alarm for sliding windows, which can be installed in a conventional window or door frame parallel to the movable window sash or door at selected distances therefrom.
Another object of this invention is to provide a portable selectively positional intruder alarm for sliding windows and doors which is installed in a conventional window frame parallel to the movable window sash or door and will activate an alarm if removed from the window or door frame.
Another object of this invention is to provide a portable selectively positional intruder alarm for sliding windows and doors which is installed in a conventional window or door frame parallel to the movable window sash or door and will activate an alarm either if the window or door is opened beyond a predetermined distance, or if it is removed from the window or door frame.
Another object of this invention is to provide a self-contained intruder alarm for sliding windows and doors, which can be quickly and easily installed in a conventional window or door frame without the use of tools and does not require any wiring.
Another object of this invention to provide a self-contained portable intruder alarm for sliding windows and doors, which is easily transported for use at various temporary locations, such as a summer home, vacation cottage, hotel or motel.
A further object of this invention is to provide an intruder alarm for sliding windows and doors which is of tubular construction and installed in existing window frames parallel to the movable window sash or door and will closely conform to the appearance of the existing window or door frame construction.
A still further object of this invention is to provide a portable self-contained intruder alarm for sliding windows and doors, which is simple in construction, inexpensive to manufacture and rugged and reliable in operation.
Other objects of the invention will become apparent from time to time throughout the specification and claims as hereinafter related.
The above noted objects and other objects of the invention are accomplished by a portable selectively positional intruder alarm for sliding windows and doors that is installed in a window or door frame with its longitudinal axis parallel to a sliding window sash or door at a selected distance therefrom to provide security while allowing the window to be partially open for ventilation and will emit an alarm either when the window or door is opened further or when the device is removed from the window or door frame. The device has a telescoping tubular housing with end plugs at each end. One end plug is fixed to the housing and the other is slidably mounted in the end of the housing. The end plugs are removably held against the opposed tracks of the sliding window sash or sliding door by the force of a compression spring within the housing. An alarm circuit disposed in the outer tube includes a battery, an audio transducer, a normally-open switch, a normally-closed switch, and may also include a visual alarm and battery condition indicator. An actuator pin on the movable frame surface of the sliding window sash or door engages the normally-open switch upon movement of the frame surface a distance toward the housing such that the partially open or fully closed window sash or door may be opened a distance less than the selected distance for ventilation without sounding the alarm and, upon further opening the window sash or door a distance approximate to the selected distance, the alarm is activated. The sliding end plug is engaged with the normally-closed switch when the device is installed in the track and, when the device is removed, is disengaged to activate the alarm.